Heh. That is childish indeed, though it wouldn't have made that much difference to the plot of the later books as far as I can see... excepting some very last minute shenanigans with the Sharans, if I remember the name right, Demandred was still mostly concerned with the Black Tower anyway even if he was a separate person from Taim.

Think about it though, how many epic fantasy series of a scope remotely comparable to WoT do you know that were finished within the intended timeframe and without a serious drop in quality? The Malazan series, maybe, though some will argue about the quality, but that one had a different approach where it was never really telling a single story with a clear beginning and end anyway, so much easier to stop at any given point. Not many others.

It's much, much more difficult to satisfactorily conclude a series of that nature than to start it up, as we've also seen with Song of Ice and Fire, or as I already mentioned in an earlier reply writers like Rothfuss and Lynch who had immensely successful starts of series, twenty years ago, but are still stuck even today and probably won't ever finish them.

Of course there's tons of completed fantasy series with no obvious drop in quality, starting with LotR, but those are generally either shorter series with fewer main characters and plotlines, or longer series with a succession of shorter story arcs or even stand-alone books, rather than one huge epic arc.

In other words, what you say may make sense in theory, but in practice I'm not convinced there is anybody that could've done that.